Question : Why does my Antivirus program not start on startup?

Hi Experts,

I am brand new to the Vista OS.  Vista either blocks my AV program and tells me I must permit it to load or it just does not load it at all and i get the message to reinstall the "crashed" application.  AV does not even start from the all programs list or desktop icon.  My current (3rd try) AV is scheduled to update definitions and then scan at each startup. (not restarts) It does this well on the many other instances of using this app on WIN XP PC's.  But Vista has changed all that for me and I am very upset after 2 days of fighting with the AV to stay on.

At first I thought it was the AV, but I am on my 3rd different  program and the same thing happens with each.  The 1st one was the highly-rated free PC Tools AV.   The next was the resource-hogging, deadly slow, but efficient Alwil Avast AV.  Finally, now  I am using the old-reliable AVG AV, not the best, but certainly dependable over the years, Until it ran into this murderous Vista.  Granted, all 3 programs are free, but very serviceable,  each with their own pros and cons.  I am new to The PC tools AV,  Vista version,  but before it was killed by Vista itself (I Believe),   it looked like it was a great freeware program like all the reviews  have said.  

So, why is Vista disabling or killing these AV programs soon after they are downloaded and installed?

                                                                              AND

What can I do to repair the situation?

I have installed and uninstalled and reinstalled and shutdown and restarted many many times over, but eventually I get the error message to reinstall the program, because it has crashed and I am left with no AV, therefore cannot go online for any potential repair.

A sub- question related to this is, how can I get Vista to stop blocking a needed program permanently?
PS: I had no problems with 3rd party Firewall APPs.

Thanks folks, in advance,

Donnie616  

Answer : Why does my Antivirus program not start on startup?

Hello Donnie616,

One thing is to make sure you're running Vista compatible versions of the virus scanners you're trying to install. If you previously downloaded a virusscanner to use on your Windows XP or previous operating sytem, you'll definately have to upgrade.
To be sure, here are the download links of the Anti-virus programs you mentioned:
http://www.pctools.com/free-antivirus/
http://www.avast.com/eng/download-avast-home.html
http://free.grisoft.com/doc/downloads-products/us/frt/0?prd=aff
In any case, make sure the virusscanner you're trying to install supports Vista and in case you're running a 64 bits version, make sure it supports it.

If you're sure your system should support the antivirus program you're installing but you're still having issues. You might want to check if any program/current virus is blocking it from starting up as that's what the average virus wants to do; avoid detection.

Regards,

LucF